LowEmissionAsphalt-136pg-WhitePaper-May2023

P a g e | 5 was lifeless as its atmosphere is thought to have been dominated by methane and ammonia, devoid of or presented little free oxygen. Ultraviolet (UV) radiation, which was the cause of the sterile Earth surface, also triggered subterranean chemical reactions with minerals. Such photoreductions of various ores created build-up in powerful, highly reactive gases then released geologically to create and maintain an atmosphere. An ongoing process, of course. Two of these gases are carbon dioxide (CO 2 ) and various forms of nitrogen (N) , which together lead to life on Earth. Primitive organisms use energy from the Sun to break down CO 2 to obtain carbon, which they incorporate into their cells to grow. The only byproduct of photosynthesis 4 is oxygen. Yet, solar-based chemical synthesis is impossible without nitrogen, the key component of chlorophyll, whose presence is required for organisms to capture sunlight. Nitrogen, through molecular, biological, and more recently industrial nitrogen fixation , is converted into various nitrogen compounds suitable for assimilation by plants namely nitrogen dioxide gas (NO 2 ) and mineralized nitrate (H-NO 3 ). One should consider both CO 2 and NO 2 -NO 3 to be invaluable natural “plant foods”. Figure 1 – Greenhouse Gas Emissions by Sector (2019) Source: Environmental Protection Agency (EPA) 4 photosynthesis is the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis, light energy is captured using nitrogen-rich chlorophyll and used to convert water, carbon dioxide, and minerals into oxygen.